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1.
Teach Teach Educ ; 1422024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38707480

RESUMO

This paper presents social validity findings from a mixed-methods study of educators who used a recently adapted online version of the research-based Double Check culturally-response practices and student engagement program. Results from 41 participants indicated that the program was easy to use, prompted them to reflect on their own culture, and that they would continue using the website. Although most users reported they would recommend the program, participants indicated they would like a wider variety of examples and more guidance for novice teachers. Additional conclusions and recommendations for improving Double Check and other online teacher professional development programs are discussed.

2.
Conserv Biol ; 36(3): e13872, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34856018

RESUMO

International demand for wood and other forest products continues to grow rapidly, and uncertainties remain about how animal communities will respond to intensifying resource extraction associated with woody bioenergy production. We examined changes in alpha and beta diversity of bats, bees, birds, and reptiles across wood production landscapes in the southeastern United States, a biodiversity hotspot that is one of the principal sources of woody biomass globally. We sampled across a spatial gradient of paired forest land-uses (representing pre and postharvest) that allowed us to evaluate biological community changes resulting from several types of biomass harvest. Short-rotation practices and residue removal following clearcuts were associated with reduced alpha diversity (-14.1 and -13.9 species, respectively) and lower beta diversity (i.e., Jaccard dissimilarity) between land-use pairs (0.46 and 0.50, respectively), whereas midrotation thinning increased alpha (+3.5 species) and beta diversity (0.59). Over the course of a stand rotation in a single location, biomass harvesting generally led to less biodiversity. Cross-taxa responses to resource extraction were poorly predicted by alpha diversity: correlations in responses between taxonomic groups were highly variable (-0.2 to 0.4) with large uncertainties. In contrast, beta diversity patterns were highly consistent and predictable across taxa, where correlations in responses between taxonomic groups were all positive (0.05-0.4) with more narrow uncertainties. Beta diversity may, therefore, be a more reliable and information-rich indicator than alpha diversity in understanding animal community response to landscape change. Patterns in beta diversity were primarily driven by turnover instead of species loss or gain, indicating that wood extraction generates habitats that support different biological communities.


Conservación de la Diversidad Alfa y Beta en Paisajes de Producción Maderera Resumen La demanda internacional de madera y otros productos forestales sigue creciendo rápidamente mientras permanecen las incertidumbres sobre cómo responderán las comunidades animales a la intensificación de la extracción de recursos asociada con la producción de bioenergía leñosa. Examinamos los cambios en la diversidad alfa y beta de murciélagos, abejas, aves y reptiles en los paisajes de producción maderera en el sureste de los Estados Unidos, un punto caliente de biodiversidad y una de las fuentes principales de biomasa leñosa a nivel mundial. Muestreamos a lo largo de un gradiente espacial de usos de suelo forestales emparejados (representando la pre- y postcosecha) que nos permitió evaluar los cambios en las comunidades biológicas resultantes de varios tipos de recolección de biomasa. Las prácticas de corta rotación y de eliminación de residuos después de la tala estuvieron asociadas con la reducción de la diversidad alfa (−14.1 y −13.9 especies, respectivamente) y una diversidad beta más baja (es decir, diferencia de Jaccard) entre los pares de uso de suelo (0.46 y 0.50, respectivamente), mientras que el raleo de rotación media incrementó la diversidad alfa (+3.5 especies) y beta (0.59). Durante la duración de una rotación permanente en una sola ubicación, la cosecha de biomasa generalmente derivó en menos biodiversidad. La respuesta de los taxones a la extracción de recursos estuvo muy mal pronosticada por la diversidad alfa: la correlación de las respuestas entre los grupos taxonómicos fue altamente variable (−0.2 a 0.4) con muchas incertidumbres. Como contraste, los patrones de diversidad beta fueron fuertemente coherentes y predecibles en todos los taxones, mientras que la correlación de las respuestas entre los grupos taxonómicos siempre fue positiva (0.05 a 0.4) con incertidumbres más limitadas. Por lo tanto, la diversidad beta puede ser un indicador más confiable y rico en información que la diversidad alfa para entender las respuestas de la comunidad animal a los cambios en el paisaje. Los patrones de la diversidad beta estuvieron impulsados principalmente por la rotación en lugar de la pérdida o ganancia de especies, lo que indica que la extracción de madera genera hábitats que mantienen a diferentes comunidades biológicas.


Assuntos
Conservação dos Recursos Naturais , Madeira , Animais , Biodiversidade , Ecossistema , Florestas
3.
Ecol Appl ; 30(7): e02155, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32358982

RESUMO

Human demand for food, fiber, and space is accelerating the rate of change of land cover and land use. Much of the world now consists of a matrix of natural forests, managed forests, agricultural cropland, and urbanized plots. Expansion of domestic energy production efforts in the United States is one driver predicted to influence future land-use and land management practices across large spatial scales. Favorable growing conditions make the southeastern United States an ideal location for producing a large portion of the country's renewable bioenergy. We investigated patterns of bat occurrence in two bioenergy feedstocks commonly grown in this region (corn, Zea mays, and pine, Pinus taeda and P. elliottii). We also evaluated potential impacts of the three major pathways of woody biomass extraction (residue removal following clearcut harvest, short-rotation energy plantations, and mid-rotation forest thinning) to bat occurrence through a priori land-use contrasts. We acoustically sampled bat vocalizations at 84 sites in the Southeastern Plains and Southern Coastal Plains of the southeastern United States across three years. We found that mid-rotation thinning resulted in positive effects on bat occurrence, and potential conversion of unmanaged (reference) forest to managed forest for timber and/or bioenergy harvest resulted in negative effects on bat occurrence when effects were averaged across all species. The effects of short-rotation energy plantations, removal of logging residues from plantation clearcuts, and corn were equivocal for all bat species examined. Our results suggest that accelerated production of biomass for energy production through either corn or intensively managed pine forests is not likely to have an adverse effect on bat communities, so long as existing older unmanaged forests are not converted to managed bioenergy or timber plantations. Beyond bioenergy crop production, mid-rotation thinning of even-aged pine stands intended for timber production, increases to the duration of plantation rotations to promote older forest stands, arranging forest stands and crop fields to maximize edge habitat, and maintaining unmanaged forests could benefit bat communities by augmenting roosting and foraging opportunities.


Assuntos
Quirópteros , Animais , Biomassa , Ecossistema , Florestas , Humanos , Sudeste dos Estados Unidos
4.
Proc Natl Acad Sci U S A ; 113(8): 1978-86, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26858425

RESUMO

Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bodies to create spatial and temporal heterogeneity in the timing, flow paths, and magnitude of network connectivity. These attributes signal a critical role for GIWs in sustaining a portfolio of landscape functions, but legal protections remain weak despite preferential loss from many landscapes. GIWs lack persistent surface water connections, but this condition does not imply the absence of hydrological, biogeochemical, and biological exchanges with nearby and downstream waters. Although hydrological and biogeochemical connectivity is often episodic or slow (e.g., via groundwater), hydrologic continuity and limited evaporative solute enrichment suggest both flow generation and solute and sediment retention. Similarly, whereas biological connectivity usually requires overland dispersal, numerous organisms, including many rare or threatened species, use both GIWs and downstream waters at different times or life stages, suggesting that GIWs are critical elements of landscape habitat mosaics. Indeed, weaker hydrologic connectivity with downstream waters and constrained biological connectivity with other landscape elements are precisely what enhances some GIW functions and enables others. Based on analysis of wetland geography and synthesis of wetland functions, we argue that sustaining landscape functions requires conserving the entire continuum of wetland connectivity, including GIWs.


Assuntos
Modelos Biológicos , Áreas Alagadas , América do Norte
5.
J Anim Ecol ; 83(1): 286-95, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23998642

RESUMO

Snakes often occur in species-rich assemblages, and sympatry is thought to be facilitated primarily by low diet overlap, not interspecific interactions. We selected, a priori, three species pairs consisting of species that are morphologically and taxonomically similar and may therefore be likely to engage in interspecific, consumptive competition. We then examined a large-scale database of snake detection/nondetection data and used occupancy modelling to determine whether these species occur together more or less frequently than expected by chance while accounting for variation in detection probability among species and incorporating important habitat categories in the models. For some snakes, we obtained evidence that the probabilities that habitat patches are used are influenced by the presence of potentially competing congeneric species. Specifically, timber rattlesnakes (Crotalus horridus) were less likely than expected by chance to use areas that also contained eastern diamond-backed rattlesnakes (Crotalus adamanteus) when the proportion of evergreen forest was relatively high. Otherwise, they occurred together more often than expected by chance. Complex relationships were revealed between habitat use, detection probabilities and occupancy probabilities of North American racers (Coluber constrictor) and coachwhips (Coluber flagellum) that indicated the probability of competitive exclusion increased with increasing area of grassland habitat, although there was some model uncertainty. Cornsnakes (Pantherophis guttatus or Pantherophis slowinskii) and ratsnakes (Pantherophis alleghaniensis, Pantherophis spiloides, or Pantherophis obsoletus) exhibited differences in habitat selection, but we obtained no evidence that patterns of use for this species pair were influenced by current interspecific interactions. Overall, our results are consistent with the hypothesis that competitive interactions influence snake assemblage composition; the strength of these effects was affected by landscape-scale habitat features. Furthermore, we suggest that current interspecific interactions may influence snake occupancy, challenging the paradigm that contemporary patterns of snake co-occurrence are largely a function of diet partitioning that arose over evolutionary time.


Assuntos
Ecossistema , Serpentes/classificação , Serpentes/fisiologia , Animais , Comportamento Alimentar , Dinâmica Populacional , Sudeste dos Estados Unidos , Especificidade da Espécie
6.
medRxiv ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38343854

RESUMO

The number of youth Emergency Department (ED) visits due to mental health concerns has been steadily increasing with a large number of youth being referred from school. Despite the increase in ED visits, there has not been an increase in the number of students who are actually admitted to the hospital. Further, youth referred from school are more likely to be discharged from the ED. Given the unique relationship between school and ED referrals and the large number of youth who do not require hospitalization, this study sought to understand how schools are supporting students who return to school after an ED visit. We conducted a scoping review to identify programs and practices to support ED to school transition. Two reviewers screened 907 manuscripts, but none of the manuscripts met the inclusion criteria. We discuss the importance of supporting students returning to school from the ED and draw from the literature on hospital to school transition to make recommendations for educators.

7.
J Sch Psychol ; 105: 101317, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876545

RESUMO

Scholars have developed culturally responsive frameworks and interventions to support educators as they aim to create inclusive and equitable classroom environments. Despite the number of frameworks on the topic, research on culturally responsive practices (CRPs) is limited by the lack of clear definitions or evidence on the effectiveness of in-classroom culturally responsive interventions. With the aim to understand which characteristics are important for in-classroom CRPs, this qualitative study explored students' perceptions of practices teachers use to respond to students' learning and cultural identities. We conducted 23 focus groups with 103 Black, Latine, and White students in middle and high school from two midwestern schools. After analyzing the data, we identified four overarching themes: (a) inclusive classroom instruction, (b) emotional safety in the classroom, (c) relational quality with the teachers, and (d) racism and other "isms" in the classroom. Students consistently commented on the importance of teacher support for students' emotional and academic well-being while also describing teachers that demeaned them or their peers, in turn, obstructing their learning. The findings hold promise to clarify and strengthen professional development CRP interventions as students offer insight about teacher cultural responsiveness and non-responsiveness.


Assuntos
Grupos Focais , Instituições Acadêmicas , Estudantes , Humanos , Estudantes/psicologia , Masculino , Feminino , Criança , Pesquisa Qualitativa , Adolescente , Competência Cultural , Professores Escolares/psicologia , Racismo
8.
Ecol Appl ; 23(1): 134-47, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23495642

RESUMO

The ecological restoration of fire-suppressed habitats may require a multifaceted approach. Removal of hardwood trees together with reintroduction of fire has been suggested as a method of restoring fire-suppressed longleaf pine (Pinus palustris) forests; however, this strategy, although widespread, has not been evaluated on large spatial and temporal scales. We used a landscape-scale experimental design to examine how bird assemblages in fire-suppressed longleaf pine sandhills responded to fire alone or fire following mechanical removal or herbicide application to reduce hardwood levels. Individual treatments were compared to fire-suppressed controls and reference sites. After initial treatment, all sites were managed with prescribed fire, on an approximately two- to three-year interval, for over a decade. Nonmetric multidimensional scaling ordinations suggested that avian assemblages on sites that experienced any form of hardwood removal differed from assemblages on both fire-suppressed sites and reference sites 3-4 years after treatment (i.e., early posttreatment). After >10 years of prescribed burning on all sites (i.e., late posttreatment), only assemblages at sites treated with herbicide were indistinguishable from assemblages at reference sites. By the end of the study, individual species that were once indicators of reference sites no longer contributed to making reference sites unique. Occupancy modeling of these indicator species also demonstrated increasing similarity across treatments over time. Overall, although we documented long-term and variable assemblage-level change, our results indicate occupancy for birds considered longleaf pine specialists was similar at treatment and reference sites after over a decade of prescribed burning, regardless of initial method of hardwood removal. In other words, based on the response of species highly associated with the habitat, we found no justification for the added cost and effort of fire surrogates; fire alone was sufficient to restore these species.


Assuntos
Aves/classificação , Aves/fisiologia , Ecossistema , Incêndios , Pinus , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental
9.
Ecol Appl ; 23(1): 148-58, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23495643

RESUMO

Measuring the effects of ecological restoration on wildlife assemblages requires study on broad temporal and spatial scales. Longleaf pine (Pinus palustris) forests are imperiled due to fire suppression and subsequent invasion by hardwood trees. We employed a landscape-scale, randomized-block design to identify how reptile assemblages initially responded to restoration treatments including removal of hardwood trees via mechanical methods (felling and girdling), application of herbicides, or prescribed burning alone. Then, we examined reptile assemblages after all sites experienced more than a decade of prescribed burning at two- to thee-year return intervals. Data were collected concurrently at reference sites chosen to represent target conditions for restoration. Reptile assemblages changed most rapidly in response to prescribed burning, but reptile assemblages at all sites, including reference sites, were generally indistinguishable by the end of the study. Thus, we suggest that prescribed burning in longleaf pine forests over long time periods is an effective strategy for restoring reptile assemblages to the reference condition. Application of herbicides or mechanical removal of hardwood trees provided no apparent benefit to reptiles beyond what was achieved by prescribed fire alone.


Assuntos
Ecossistema , Incêndios , Pinus , Répteis/classificação , Répteis/fisiologia , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental
10.
J Sch Psychol ; 98: 61-77, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37253583

RESUMO

Disparities in exclusionary discipline practices are well-documented; however, variation in Black students' disciplinary experiences across different racial and ethnic school compositions remains understudied. Utilizing a state-wide dataset (N = 769,050 students in J = 1296 schools), we examined student- and school-level factors that contribute to suspensions for Black students across schools with varying racial and ethnic diversity. Consistent with prior research, we found that Black students were disproportionately suspended more often, for more days, and more likely for soft offenses. We also found that students in majority Black schools (i.e., those where >50% of the students were Black) had the highest unadjusted rates of suspension. However, when controlling for multiple other student- and school-level characteristics, including overall suspension rates, we found that Black students attending majority White schools had a higher adjusted risk of suspension than in majority Black or heterogenous diverse schools, suggesting higher rates of differential treatment in White majority schools. We discuss the implications of these results and the role school psychologists play in supporting professional development, training, and data-based decision making to reduce disproportionality.


Assuntos
Negro ou Afro-Americano , Punição , Estudantes , Humanos , Instituições Acadêmicas , Fatores Socioeconômicos , Minorias Étnicas e Raciais
11.
J Wildl Dis ; 59(1): 176-180, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36584345

RESUMO

Understanding risk factors associated with reintroductions is important for making informed decisions within an adaptive framework. Biosecurity measures minimizing the risk of the introduction or spread of transmissible diseases are a priority when considering the release of captive-reared wildlife. Eastern indigo snake (EIS; Drymarchon couperi) reintroductions have been occurring in Alabama since 2010 and in Florida since 2017. During this effort the pathogen Cryptosporidium serpentis was detected, affecting several of the captive breeding snakes. Infected snakes were quarantined and removed from breeding efforts, which reduced snakes available for the reintroduction projects. To make informed management decisions about future reintroduction strategies, 155 free-ranging snakes were sampled at the two release sites and a third site in Georgia to evaluate the natural occurrence of C. serpentis. Additionally, 72 free-ranging EIS and other species incidentally encountered throughout the EIS range were tested opportunistically. All snakes sampled at the three focal sites tested negative, but one opportunistically tested EIS from South Florida tested positive. These results indicate that C. serpentis is present in the environment in at least one location, but at low levels. Our results suggest that, pending additional surveillance, C. serpentispositive snakes should not be included in reintroduction efforts, and that maintaining a high level of biosecurity is important in captive breeding programs.


Assuntos
Colubridae , Criptosporidiose , Cryptosporidium , Animais , Criptosporidiose/epidemiologia , Serpentes , Animais Selvagens , Georgia
12.
Ecol Appl ; 22(4): 1084-97, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22827120

RESUMO

Habitat loss and degradation are thought to be the primary drivers of species extirpations, but for many species we have little information regarding specific habitats that influence occupancy. Snakes are of conservation concern throughout North America, but effective management and conservation are hindered by a lack of basic natural history information and the small number of large-scale studies designed to assess general population trends. To address this information gap, we compiled detection/nondetection data for 13 large terrestrial species from 449 traps located across the southeastern United States, and we characterized the land cover surrounding each trap at multiple spatial scales (250-, 500-, and 1000-m buffers). We used occupancy modeling, while accounting for heterogeneity in detection probability, to identify habitat variables that were influential in determining the presence of a particular species. We evaluated 12 competing models for each species, representing various hypotheses pertaining to important habitat features for terrestrial snakes. Overall, considerable interspecific variation existed in important habitat variables and relevant spatial scales. For example, kingsnakes (Lampropeltis getula) were negatively associated with evergreen forests, whereas Louisiana pinesnake (Pituophis ruthveni) occupancy increased with increasing coverage of this forest type. Some species were positively associated with grassland and scrub/shrub (e.g., Slowinski's cornsnake, Elaphe slowinskii) whereas others, (e.g., copperhead, Agkistrodon contortrix, and eastern diamond-backed rattlesnake, Crotalus adamanteus) were positively associated with forested habitats. Although the species that we studied may persist in varied landscapes other than those we identified as important, our data were collected in relatively undeveloped areas. Thus, our findings may be relevant when generating conservation plans or restoration goals. Maintaining or restoring landscapes that are most consistent with the ancestral habitat preferences of terrestrial snake assemblages will require a diverse habitat matrix over large spatial scales.


Assuntos
Ecossistema , Modelos Biológicos , Serpentes/fisiologia , Animais , Demografia , Monitoramento Ambiental , Serpentes/classificação , Sudeste dos Estados Unidos , Especificidade da Espécie
13.
PLoS One ; 14(4): e0214845, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30951541

RESUMO

Upper respiratory tract disease (URTD) in North American tortoises (Gopherus) has been the focus of numerous laboratory and field investigations, yet the prevalence and importance of this disease remains unclear across many tortoise populations. Furthermore, much research has been focused on understanding diagnostic biomarkers of two known agents of URTD, Mycoplasma agassizii and Mycoplasma testudineum, yet the reliability and importance of these diagnostic biomarkers across populations is unclear. Gopher Tortoises (Gopherus polyphemus) have experienced significant declines and are currently protected range wide. Geographically, Alabama represents an important connection for Gopher Tortoise populations between the core and periphery of this species' distribution. Herein, we systematically sampled 197 Gopher Tortoises for URTD across seven sites in south-central and south-eastern Alabama. Plasma samples were assayed for antibodies to M. agassizii and M. testudineum; nasal lavage samples were assayed for the presence of viable pathogens as well as pathogen DNA. Lastly, animals were scored for the presence of external symptoms and nasal scarring consistent with URTD. External symptoms of URTD were present in G. polyphemus in all sites sampled in Alabama. There was no relationship between active symptoms of URTD and Mycoplasma antibodies, however the presence of URTD nasal scarring was positively related to M. agassizii antibodies (P = 0.032). For a single site that was sampled in three sequential years, seroprevalence to M. agassizii significantly varied among years (P < 0.0001). Mycoplasma agassizii DNA was isolated from four of the seven sites using quantitative PCR, yet none of the samples were culture positive for either of the pathogens. An analysis of disease status and condition indicated that there was a significant, positive relationship between the severity of URTD symptoms and relative body mass (P < 0.05). This study highlights the need for continued monitoring of disease in wild populations. Specifically, focus must be placed on identifying other likely pathogens and relevant biomarkers that may be important drivers of URTD in North American tortoises. Special consideration should be given to environmental contexts that may render wild populations more susceptible to disease.


Assuntos
Infecções por Mycoplasma/veterinária , Infecções Respiratórias/veterinária , Tartarugas/microbiologia , Alabama , Animais , Anticorpos Antibacterianos/sangue , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Masculino , Mycoplasma/genética , Mycoplasma/imunologia , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/microbiologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/microbiologia
14.
Ecol Evol ; 7(16): 6271-6283, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28861231

RESUMO

Population genetic diversity is widely accepted as important to the conservation and management of wildlife. However, habitat features may differentially affect evolutionary processes that facilitate population genetic diversity among sympatric species. We measured genetic diversity for two pond-breeding amphibian species (Dwarf salamanders, Eurycea quadridigitata; and Southern Leopard frogs, Lithobates sphenocephalus) to understand how habitat characteristics and spatial scale affect genetic diversity across a landscape. Samples were collected from wetlands on a longleaf pine reserve in Georgia. We genotyped microsatellite loci for both species to assess population structures and determine which habitat features were most closely associated with observed heterozygosity and rarefied allelic richness. Both species exhibited significant population genetic structure; however, structure in Southern Leopard frogs was driven primarily by one outlier site. Dwarf salamander allelic richness was greater at sites with less surrounding road area within 0.5 km and more wetland area within 1.0 and 2.5 km, and heterozygosity was greater at sites with more wetland area within 0.5 km. In contrast, neither measure of Southern Leopard frog genetic diversity was associated with any habitat features at any scale we evaluated. Genetic diversity in the Dwarf salamander was strongly associated with land cover variables up to 2.5 km away from breeding wetlands, and/or results suggest that minimizing roads in wetland buffers may be beneficial to the maintenance of population genetic diversity. This study suggests that patterns of genetic differentiation and genetic diversity have associations with different habitat features across different spatial scales for two syntopic pond-breeding amphibian species.

15.
Nat Geosci ; 10(11): 809-815, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30079098

RESUMO

Governments worldwide do not adequately protect their limited freshwater systems and therefore place freshwater functions and attendant ecosystem services at risk. The best available scientific evidence compels enhanced protections for freshwater systems, especially for impermanent streams and wetlands outside of floodplains that are particularly vulnerable to alteration or destruction. New approaches to freshwater sustainability - implemented through scientifically informed adaptive management - are required to protect freshwater systems through periods of changing societal needs. One such approach introduced in the US in 2015 is the Clean Water Rule, which clarified the jurisdictional scope for federally protected waters. However, within hours of its implementation litigants convinced the US Court of Appeals for the Sixth Circuit to stay the rule, and the subsequently elected administration has now placed it under review for potential revision or rescission. Regardless of its outcome at the federal level, policy and management discussions initiated by the propagation of this rare rulemaking event have potential far-reaching implications at all levels of government across the US and worldwide. At this timely juncture, we provide a scientific rationale and three policy options for all levels of government to meaningfully enhance protection of these vulnerable waters. A fourth option, a 'do-nothing' approach, is wholly inconsistent with the well-established scientific evidence of the importance of these vulnerable waters.

16.
J Environ Qual ; 35(5): 1924-38, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16973634

RESUMO

To determine useful metrics for assessing stream water quality in the Southeastern Coastal Plain, we examined differences among two buffered and three unbuffered streams in an agricultural landscape in southwestern Georgia. Potential indicators included amphibian diversity and abundance, aquatic macroinvertebrate populations, riparian vegetative structure, water quality, and stream physical parameters. Variability among sites and treatments (buffered vs. unbuffered) existed, with sites in the same treatment as most similar, and disturbances from a nearby eroding gully strongly affecting one unbuffered site. Of the invertebrate metrics examined, percentages of clingers, Ephemeroptera-Plecoptera-Trichoptera (EPT), Elmidae (Coleoptera), Crustacea (Decapoda and Amphipoda), and dipterans were found to be possible indicators of stream health for perennial streams within this region. Overall, buffered sites showed higher percentages of sensitive invertebrate groups and showed lower and more stable concentrations of nitrate N, suspended solids, and fecal coliforms (FCs). Percent canopy cover was similar among sites; however, riparian vegetative coverage and percent leaf litter were greatest at buffered sites. No differences in amphibian abundance, presence, and absence within the riparian area were apparent between sites; however, instream larval salamanders were more abundant at buffered streams. In this study, stream buffers appeared to decrease nutrient and sediment loads to adjacent streams, enhancing overall water quality. Selected benthic macroinvertebrate metrics and amphibian abundance also appeared sensitive to agricultural influences. Amphibians show potential as indicator candidates, however further information is needed on their responses and tolerances to disturbances from the microhabitat to landscape levels.


Assuntos
Anfíbios , Criação de Animais Domésticos , Ecossistema , Invertebrados , Rios , Movimentos da Água , Anfíbios/crescimento & desenvolvimento , Animais , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Georgia , Invertebrados/crescimento & desenvolvimento
17.
J Med Entomol ; 39(2): 398-403, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11931042

RESUMO

The male and female of Amblyomma geochelone n. sp. are described and illustrated by both scanning electron micrographs and line drawings. Specimens of this new tick species were recovered from the endangered ploughshare tortoise, Geochelone yniphora (Vaillant), in northwestern Madagascar. This relatively large tick is morphologically most similar to Amblyomma nuttalli Dönitz, which occurs in mainland sub-Saharan Africa where it mainly parasitizes other species of tortoises. However, several characters distinguish the new species from A. nuttalli including the scutal ornamentation in both sexes and the characteristic patterns of shallow grooves on the alloscutum of the female of A. geochelone. Because the adult stages of A. geochelone are almost certainly host specific ectoparasites of the ploughsh are tortoise, this new tick species is also probably endangered.


Assuntos
Ixodidae/classificação , Infestações por Carrapato/veterinária , Tartarugas/parasitologia , Animais , Feminino , Ixodidae/anatomia & histologia , Masculino , Infestações por Carrapato/parasitologia
18.
J Wildl Dis ; 50(4): 745-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25121399

RESUMO

Abstract From 2011-12, we studied a gopher tortoise (Gopherus polyphemus) population with a historically high prevalence of antibodies to Mycoplasma agassizii to assess long-term effects of upper-respiratory-tract disease (URTD) on tortoise behavior. We radiotracked 30 adult tortoises (16 males, 14 females) from a long-term study site with the use of mark-recapture methods to determine site fidelity and to compare home-range size to that of a study in 1997. An additional 10 tortoises (six males, four females) with severe clinical signs of URTD from elsewhere in the study area were radiotracked and compared to tortoises that were asymptomatic or had only mild clinical signs. We also monitored thermoregulatory behavior of tortoises with the use of data loggers affixed to the carapace. There was no significant difference in home-range size between the asymptomatic tortoises and those with mild symptoms. Home ranges of tortoises with severe URTD were significantly larger than asymptomatic or mildly affected tortoises. Tortoises with severe clinical signs moved long distances over short periods, contradicting a hypothesis that chronically infected tortoises are less likely to emigrate. Prevalence of M. agassizii antibodies was similar among the three groups (98% overall), but prevalence of antibodies to a second pathogen associated with URTD, Mycoplasma testudineum, was lower in the asymptomatic (n=14, 7%) and mild-symptoms (n=7, 14%) groups than the severe-symptoms group (n=8, 50%). Variation in the average carapacial temperatures of tortoises with severe URTD was significantly different from carapacial temperatures of mild and asymptomatic tortoises, suggesting differences in thermoregulatory behavior of severely ill tortoises. Our 15-yr recapture data suggest that, despite high prevalence of M. agassizii, population density has not decreased over time. However, emigration, especially of tortoises with severe clinical disease, may play an important role in dispersal and persistence of pathogens.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Atividade Motora , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Infecções Respiratórias/veterinária , Tartarugas , Animais , Comportamento Animal , Feminino , Georgia/epidemiologia , Masculino , Infecções por Mycoplasma/epidemiologia , Vigilância da População , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia
19.
J Wildl Dis ; 50(4): 733-44, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25098305

RESUMO

Abstract Upper respiratory tract disease (URTD) in the gopher tortoise (Gopherus polyphemus) is highly contagious and has been implicated in the reduction of populations throughout the range. With the exception of a few limited studies, the prevalence of URTD in Georgia, USA tortoise populations is poorly known. We found that exposure to Mycoplasma agassizii and Mycoplasma testudineum, associated with URTD, varied geographically among 11 Georgia tortoise populations. The prevalence of antibodies to M. agassizii in individual populations was either very low (0-3%, n=7 populations) or very high (96-100%, n=4 populations), whereas there was variation in the prevalence of antibodies to M. testudineum among populations (20-61%, n=10) with only one site being negative. Five sites had tortoises with antibodies to both pathogens, and these were the only sites where we observed tortoises with clinical signs consistent with URTD. We did not find tortoises with clinical signs of URTD at sites with tortoises with antibodies only to M. testudineum, which provides evidence that this organism may be of limited pathogenicity for gopher tortoises. Collectively, these data indicate that both M. agassizii and M. testudineum are present in Georgia populations of gopher tortoises and that clinical disease is apparent in populations where both pathogens are present. Additional research is needed to better understand the role of these two pathogens, and other potential pathogens, in the overall health of tortoise populations, especially if future conservation efforts involve translocation of tortoises.


Assuntos
Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Infecções Respiratórias/veterinária , Tartarugas , Animais , Feminino , Georgia/epidemiologia , Masculino , Infecções por Mycoplasma/epidemiologia , Vigilância da População , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia
20.
Sci Total Environ ; 445-446: 219-30, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23333518

RESUMO

Previous research has documented the ubiquity of human and veterinary pharmaceuticals and personal care products (PPCPs) in freshwater, though their persistence and transport is relatively unknown. The objective of this study was to quantify the abundance and transport of human and veterinary PPCPs in a rural, central Indiana stream influenced by confined animal feeding operations (CAFOs). Research objectives also aimed to identify mechanisms controlling abundance and transport. PPCP concentrations and stream physicochemical characteristics were measured monthly over one year at multiple sites along a 60 km reach. Overall, human PPCPs were more abundant and measured at higher concentrations than veterinary pharmaceuticals. Veterinary pharmaceutical concentrations (lincomycin, sulfamethazine) were greatest in stream reaches adjacent to CAFOs. No distinct spatial variation was observed for human PPCPs. However, caffeine and paraxanthine had significant temporal variation with higher concentrations in winter. In contrast, DEET had higher concentrations in summer. Pharmaceutical load (µg/s) ranged from<0.005 to 1808 µg/s across sites, sampling events and pharmaceutical compounds with human PPCPs having higher loads relative to veterinary pharmaceuticals. Reach input ranged from net retention (sulfamethazine in August) to 1667 µg/m/d paraxanthine in March. Triclosan had the highest measured mean input into the reach (661 µg/m/d) and sulfamethazine had the lowest mean input (32 µg/m/d). Across measured compounds, input of PPCPs into the reach was two orders of magnitude lower than nitrate-N input (57,000 µg/m/d). Transport metrics indicated acetaminophen and caffeine are transported farther than triclosan though had lower loss velocities (loss relative to abundance). Loss rate of PPCPs was an order of magnitude lower than nitrate-N loss rate. Human PPCPs were more abundant than veterinary pharmaceuticals in this rural watershed influenced by CAFOs. Further, concentrations had significant temporal and spatial variation highlighting differential sources and fates. Thus, mechanisms driving PPCP retention and transport need to be identified to aid management of these emerging contaminants.


Assuntos
Rios/química , Drogas Veterinárias/análise , Poluentes Químicos da Água/análise , Qualidade da Água , Criação de Animais Domésticos , Animais , Humanos , Indiana , Movimentos da Água
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